1966 Bronco Trans Swap, 3 on the tree to C4 Automatic

[cainesbronco]

Hi all! First off- this forum is a life saver, so I appreciate everyones advice, input, etc.

I have a 1966 with a 170 engine and 3 on the tree manual transmission.... the engine is okay but trans is shot and I want to swap it with C4 auto transmission. Running with a 2" lift and 32in tires. Just using as a weekend cruiser, beach truck and coffee drives.

A couple questions:
1. I have access to a fresh C4 auto trans from a Ford Truck, or a rebuilt one from a previous Bronco... will either of these set ups be a pretty simple swap into the Bronco behind the 170? What modifications would need to happen?
2. I also have access to a full 302 and auto C4 from a 72 f100 that I can swap in, would this 302 and C4 combination be a more suitable swap? Im open to putting the bigger engine in.

Thanks!

 

[okie4570]

Are either of those possible donor C4 transmissions from a 4x4 or are they 2WD?

 

[cainesbronco]

Are either of those possible donor C4 transmissions from a 4x4 or are they 2WD?
from 2WD

 

[thegreatjustino]

Any Ford truck C4 is going to be two wheel drive. The only 4x4 C4 came in the Bronco. From your list you have access to one two wheel drive transmission and one four wheel drive transmission.

Neither will bolt up to the 170 with the V8 bellhousing they likely have on them already.

You would need the inline six bellhousing to C4 that would have come in a mustang (or other Ford car) with a 170/200 inline six engine.

Even if you find the correct bellhousing and swap it onto the C4, installing it into the Bronco will push your whole drivetrain back several inches. You'll need to drill new holes in the frame for mounting the cross member, figure out shifter linkages, and get new driveshafts.

If you swap in an entire V8 and C4 assembly as you mention in #2, the C4 again is going to be two wheel drive, so won't really work without rebuilding the transmission and converting it to 4x4 with the correct main shaft.

If you want to take the 302 from option #2 and mate it with the Bronco transmission from option #1, that will give you the correct V8 engine and C4 to install in a Bronco. However, going from an inline six to a V8 required cutting the inline six mounting horns off the frame and welding V8 ones on in the correct locations. V8 uses a different radiator, core support, throttle linkage, air cleaner, etc, etc, etc.

Neither of the options you're exploring are a simple drop in. Both will require sourcing other parts and some type of fabrication work. Both are doable, but are fairly major projects. Plus ensuring you have the right combination of parts.

 

[bronco italiano]

Make sure the bronco transmission pan has the dimple in it with the proper extended pickup tube

 

[cainesbronco]

Make sure the bronco transmission pan has the dimple in it with the proper extended pickup tube

Is this referring to the trans when connecting to I-6 or the 302 ? or either

 

[bmbm]

https://fordsix.com/threads/need-help-finder-a-starter-motor-for-my-170ci-bronco-build.85324/

This guy is working on a C4 swap although it is unclear to me if he is building a 2wd Bronco. It's for his mom. Might be something helpful here for you.
The later and hard to find 200 6 from 81-83? can be made to fit any sbf trans/bh as far as I know. The 200 will just plop right in as basically same as 170. Much easier, cheaper and less time consuming than a v8 swap.